Spot Painting … Melting-in the paint edges.
By Carl Brunson
Back in the late 60’s when I was learning to paint cars, we used acrylic lacquer and regular, not acrylic enamel … oh yeah, I can almost hear you guys thinking: Oh great, Old Carl is on another nostalgia kick and he is going to rant on about “way back when” again. Well, yes and no. Thinking about blending paint takes me back to the good ‘ol lacquer days when I did it every day… several times a day.
Acrylic lacquer can be melted into old acrylic lacquer making a perfect repair. The rule was that you could paint enamel over lacquer, but you couldn’t put lacquer over enamel because it wouldn’t melt in, or in the case of a repainted car, lift and wrinkle the enamel. Because only GM cars came from the factory with acrylic lacquer … the lacquer over enamel rule was basically ignored. We painters learned how to wet the edge of the lacquer to the point it needed little or no polishing and would bite enough into the panel without peeling because we rubbed the blend area with rubbing compound. That gave the lacquer compound scratches to bite into.
Not only can lacquer be painted out in the shop, it is a many times faster paint repair than enamel. For painters being paid on commission, the faster the work got done, the larger your paycheck was. For several years I worked in a shop that did the warranty work for a Ford Dealership. At least 80% of that warranty work was done with lacquer. There were countless non-GM cars running around with my “break the rules” lacquer spot jobs on them.
So, in the early 80’s when the urethane base/coat clear/coat paint systems were being introduced and they told me I couldn’t wet the edges of the clear down. That I had to paint complete panels … did I listen? Nope! I did make quite a few messes before I figured out what slow reducers would make a slick looking clear blend on a sail panel so I didn’t have to get into clearing the roof along with the quarter panel. Sikkens paint came out with a solvent called SRA that you sprayed on the blend area before painting, that softened the old paint and then you sprayed the clear edge with SRA again and the clear edge just disappeared. These days every paint company has a blending solvent. Some blenders even come in rattle cans now!
So, I bet you are wondering why the “wet the edge down” repairs are not as popular as complete panel painting if it works well. Several things come into play here. The major one being that the wet down edge of the clear or single stage color is very thin and doesn’t seem to hold up as well to the sun and everyday use. The other thing I can think of is that it is a spooky thing to do for the painter. The blending solvents are a very slow reducer and just a little bit too much or if the day is just a little cool … that clear edge you are trying to melt into the old paint can curdle up or turn into a big run that will cause you to have to redo the job. Sometimes it is a lot smarter to take the time to paint a larger area than to take the chance of having to redo a job.